E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
according to fable, may be obtained in a multitude of ways. For example:
Albrics cloak, called Tarnkappe (3 syl.), which Siegfried got possession of, rendered him invisible. (Nibelungen Lied.)
A chamelon carried in the breast will render a person invisible.
A capon stone, called Alectora, will render any person invisible who carries it about his person. (See MIRROR OF STONES.)
A dead hand. It is believed that a candle placed in a dead mans hand
gives no light to any but those who use it. (See HAND.)
Fern-seed, mentioned by Shakespeare, and by Beaumont and Fletcher, possesses the same charm.
Gyges ring, taken from the flanks of a brazen horse, made the wearer invisible, provided he turned the ring inwards.
Heliotrope, mentioned by Boccaccio in his Decamron (Day viii. 3), is a green stone, which renders a person invisible. So does the herb called heliotrope, according to Solnus, who says, Herba etiam ejusdem nomnis cum, a quocumque gestabtur, subtrahit visibus obvirum. (Georgic, xl.)
The helmet of Perseus (2 syl.) and the helmet of Pluto (called Orci Gala), both rendered the wearer invisible. (Classic story.)
The helmet which Pluto gave to the Cyclops made them invisible whenever it was worn.
Jack the Giant-killer had a cloak of invisibility as well as a cap of knowledge.
Kepleins mantle. The mantle of Hel Keplein, which belonged to the dwarf-king Laurin, rendered the wearer invisible. (The Heldenbuch; thirteenth century.)
The Moros Musphoron was a girdle of invisibility. (Mrs. Centlivre: A Bold Stroke for a Wife.)
Otnits ring. The ring of Otnit, King of Lombardy, according to the Heldenbuch, possessed a similar charm.
Reynards wonderful ring had three colours, one of which (the green) caused the wearer to become invisible. (Reynard the Fox, 1498.)